It is known from U.S. Pat. No. 3,007,409 to provide an explosive cartridge for industrial tools in which a plug or gas check containing a detonating primer is positioned near the base of the cartridge shell with the powder between the plug and base. The primer is positioned in the end of the plug facing the open end of the shell and is detonated by a firing pin on a ram entering the shell from the open end. The gases from the ignited powder pushes on the ram which engages a work piece.
It is also known from U.S. Pat. No. 3,155,039 to provide forwardly projecting prongs on the plug or gas check and which are disposed about the primer. The prongs resist compression and thus protect the primer from accidental engagement and detonation by a rearwardly moving first pin. However, the prongs are readily bent over sideways by a rotary motion between the prongs and firing pin and thus permit engagement and detonation.
It is now proposed to provide an improved cartridge having therein a gas check which deforms during the detonation thereof to trap and retain the primer.